ok, i just read a whole bunch of posts on how much boost before our stock injectors max out and a bunch more about high egt's.
Normally i'm pretty nice to my car so egt's don't go over 1400 too often, but i went to the track the other day so in running this obviously changed. here's the results: http://forums.2gnt.com/dcboard.php?az=show_mesg&forum=11&topic_id=5012&mesg_id=5012&page=

As for maxing out the injectors, some people said over 7psi and their pretty much done for and others said they were fine all the way up to 10psi, so is there a general consensus?

I was hoping that i could lower my egt's just by throwing in some bigger injectors but is their anything else that can cause high egt's aside from the limits of our stock injectors?

I'm still on stock exhaust can that also cause you to see higher egt's?

Oh yeah for those that are wondering, i've got the egt tapped into the #4 runner on the star manifold (closest to the driver side) that is where you are supposed to get the hottest readings from what i remember reading correct

I would like to be able to run my car and actually stay on the gas until i cross the line, but i just didn't want to do it the other day with 1600 degree egt's b/c i figured a few 10ths of a second wasn't worth a melted piston

Add more fuel.

I'm of the opinion you shouldn't run stock injectors on any turbokit. Get at least some 30#/310cc's in there and you'll be in much better shape. They're only $100 for a set of 4, can't go wrong there.

The stock exhaust will hurt a little, but not nearly as much as running lean. For now, richen up your SFMU if you have one, or if not, raise the idle pressure a few psi if possible. The EGT's don't tell the whole story, you may be detonating your pistons to death long before they melt if you're running too lean.

more fuel, more timing, less restrictive exhaust, water/alcohol injection, block off EGR, better/water cooled Intercooler...


Brian

nevermind.

o yeah forgot to add, i have sfmu and after my second run raised idle fp to 55-56 psi

Change your fuel filter..it dropped my EGTs about 25-50 degrees CELSIUS. It was really dirty, I couldn't believe it. But then I put a stock GST back on (origanlly had a 2.5" catback). I need a 3" now, I'm kinda getting tired of openning my cutout everytime I boost - can't feel the boost kick in.

Alvin

Yea change the filter and get some more fuel in there.....or else.

filter's new and the idle fp is as high as i can make it i think i guess i'll be getting new injectors over the winter, but thanks for all the input guys

idle FP is 47. why is yours higher?

Originally posted by Blizare
idle FP is 47. why is yours higher?

according to hahn idle fp should be between 47 and 55, raising the baseline to 55 means higher fp at full boost

Ack... the SFMU is *so* much more versatile than just raising/lowering the idle pressure. If you don't have the center port bleed valve hooked up, get one!


This will allow you to run a steeper disk/ring set and allow adjustment of the fuel curve on the top end. I believe you want around 100psi fuel pressure at 8psi (please search to be sure), and a stock fuel pressure from idle-0vac.

Either search and read every single SFMU tuning post on 2gnt, read the Vortech manuals, or find someone that knows their way around them to set it up for you.

by steeper do you mean greater than a 12:1 rate, currently i have the largest disk no ring and the dark spring because that seems to be the common consensus for what is best for stock injectors. I do believe it is easily hitting the 100psi, but i read in another post something about fp being maxed out around 110psi and to me that means if you were to need say 120psi then you'd be leaning out at full boost b/c your fp can't go any higher, i guess i'll do some more reading on the sfmu, but i really don't want to see any higher fp's so i think i may just spring for larger injectors, i'm not really worried about it right now b/c i usually don't boost that much and never do long pulls to get my egts that high

You're probably right, it's been so long since I've done the math for stock injectors I really don't remember. All I remember is there was like a 5% margin of error... you can just barely achieve enough flow through the stockers to give you 8psi if everything was working right.

I'd personally spend the $100 bucks and worry about running too rich, rather than worrying about running lean and detonating and/or melting things.

do you have a FP gauge?

I couldn't get my FP any higher than 80 psi with the largest disk/no ring dar spring combo. :shrug

Originally posted by Blizare
do you have a FP gauge? I couldn't get my FP any higher than 80 psi with the largest disk/no ring dar spring combo. :shrug

With the largest disk you should be rising 10-12 psi of fuel pressure for 1 psi of boost pressure seen by the SFMU. If you're not there is probably something a little wrong (or you're using the bleed screw to bleed off pressure).

BTW for the record, FP on 96+ 2gnt (late model fuel system) is 52psi. This is idle, static, AND under driving conditions (unless you're turbo with an FMU or something of that sort) as there is no vacuum signal routed to the FPR that is located by the fuel tank.

I have some accel 30Lb injectors you can have for 75$ shipped

Originally posted by Blizare
do you have a FP gauge? I couldn't get my FP any higher than 80 psi with the largest disk/no ring dar spring combo. :shrug

yes but its just mechanical, when i installed the sfmu and walbro i just hooked an air pump up to the line to make sure it raised fp and it easily went to 100+ psi I had already tested the air pump out to see that it gave about the equivalent of 7-8 psi
i am definetly planning on getting bigger injectors to be on the safe side though

Originally posted by willmayo
I have some accel 30Lb injectors you can have for 75$ shipped

no cash right now, damn holidays but after december 25th if you still have em i might take them, right now i'm trying to decide what size injectors i want though, 330's, 440's or somethin in between